Antioxidants in the cardiac cells. The major antioxidants are glutathione (GSH)/oxidized glutathione (GSSG) along with the enzymes glutathione reductase (GRed) and glutathione peroxidase (GPx), catalase, superoxide dismutase (SOD), NADPH oxidase, and α-tocopherol and vitamin C. MITO, mitochondria; RCOO• and RCOOH, lipid radical and lipid; α-toco• and α-toco, α-tocopheroxyl radical and α-tocopherol.